Iron-type golf club head and method for manufacturing it

ABSTRACT

An iron-type golf club head incorporating one or more internal chambers provided in the top portion of a perimeter weighted iron club head is provided. The golf club head has a face plate defining a striking face of the club head and a body having an annular mass disposed behind the striking face. The annular mass extends about a periphery of the face plate defining an external cavity centrally located on a rear side of the face plate. The annular mass includes a top portion extending along a top edge of the face plate, a toe portion extending along a toe edge of the face plate, a heel portion, and a bottom portion. At least one internal chamber is located adjacent to the top edge, as defined by the top portion of annular mass. The internal chamber, or a selected number of a plurality of internal chambers defined by the annular mass, can be filled to further manage the weight distribution of the club head. Thus, the club head can be tuned to accommodate requirements of an individual golfer.

BACKGROUND OF THE INVENTION

[0001] The present invention relates generally to golf club heads and,more particularly, to iron-type golf club heads.

[0002] The weight distribution of a club head is an important designconsideration. Many iron-type golf club heads are configured in what iscommonly known as “cavity back” design. Such designs allocate weightabout the club's periphery. This peripheral weighting is generallyconsidered to provide greater forgiveness for off-center shots thantraditional blade-style club heads. As such, cavity back designs oftenare preferred by high handicap golfers.

[0003] Another, sometimes competing, consideration relates to thelocation of the club head's center of gravity (CG). A club having a lowCG location is often preferred many players, typically less skilledplayers, for the increased ease in launching a golf ball. Alternatively,in the hands of an experienced golfer, a club head having a morecentrally located CG provides greater control over the flight of theball. Most product lines of club heads have a fixed weight distribution;consequently, very little can be done to tune the weight distribution ofa club head to the particular needs of an individual golfer. Toaccommodate golfers across all skill levels, golf club manufacturerstypically must carry several distinct product lines of golf clubs, whichcan increase production costs.

[0004] It should, therefore, be appreciated that there exists a need foran iron-type golf club head having weight allocated about its peripheryand a low center of gravity for improved forgiveness for off-centershots, while providing an adaptable weight distribution profile toaccommodate requirements of an individual golfer. The present inventionfulfills this need and others.

SUMMARY OF THE INVENTION

[0005] A golf club head in accordance with the present inventionincorporates one or more internal chambers provided in at least aportion of the top portion of a perimeter weighted iron club head. Theclub head includes a face plate having a front side defining a strikingface of the club head and a body having an annular mass disposed behindthe striking face. The annular mass extends about a periphery of theface plate defining an external cavity centrally located on a rear sideof the face plate. The annular mass includes a top portion extendingalong a top edge of the face plate, a toe portion extending along a toeedge of the face plate, a heel portion, and a bottom portion. Aninternal chamber is located adjacent to the top edge, as defined by thetop portion of annular mass.

[0006] The single chamber, or a selected number of a plurality ofchambers defined by the annular mass, can be filled with a polymer, foamor high density filler, for example, to further manage the weightdistribution of the club head. If the top chamber or chambers are leftunfilled, lowering of the center of gravity (CG) of the head ismaximized. A low CG is preferred by many golfers for the added ease inlaunching a golf ball. If the heel portion of a plurality of chambers inthe top portion are filled, then the CG is moved toward the heel. Thislow, heelward CG location is preferred by many players for the ease oflaunch and ease of promoting right to left ball flight (slicereduction). Alternatively, extreme end chambers at the heel and toe canbe filled to achieve increased heel and toe weighting. Thus, the clubhead can be tuned to accommodate requirements of an individual golfer.

[0007] A separate face plate is preferably attached at the front of thehead to close and conceal the chamber or chambers.

[0008] Preferably, a metal main body of the club head is cast with thechambers formed in the top portion and a metal face plate is welded tothe front. Adhesive, press-fitting and other joining techniques may alsobe used for attaching the face plate. Alternatively, an integrallyformed club head with chambers at least in the top portion can be formedusing techniques employing ceramic cores, soluble cores or pick-outs asknown to those skilled in the art.

[0009] For purposes of summarizing the invention and the advantagesachieved over the prior art, certain advantages of the invention havebeen described herein above. Of course, it is to be understood that notnecessarily all such advantages may be achieved in accordance with anyparticular embodiment of the invention. Thus, for example, those skilledin the art will recognize that the invention may be embodied or carriedout in a manner that achieves or optimizes one advantage or group ofadvantages as taught herein without necessarily achieving otheradvantages as may be taught or suggested herein.

[0010] All of these embodiments are intended to be within the scope ofthe invention herein disclosed. These and other embodiments of thepresent invention will become readily apparent to those skilled in theart from the following detailed description of the preferred embodimentshaving reference to the attached figures, the invention not beinglimited to any particular preferred embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Embodiments of the present invention will now be described, byway of example only, with reference to the following drawings in which:

[0012]FIG. 1 is an exploded front view of a first preferred embodimentof a club head in accordance with the invention, depicting a face plateand a rear weight removed from a main body.

[0013]FIG. 2 is a front perspective view of a main body of a secondpreferred embodiment of a club head in accordance with the invention,having multiple hollow chambers in the top and toe portions of the clubhead.

[0014]FIG. 3 is a vertical cross-section of the main body of FIG. 1.

[0015]FIG. 4 is a vertical cross-section of a main body of anotherpreferred embodiment.

[0016]FIG. 5 is a cross-section of a mold for use in a preferred methodof the present invention.

[0017]FIG. 6 is a front view of one part of the mold of FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] With reference to the illustrative drawings, and particularly toFIG. 1, there is shown a club head 10 having a cast metal body 12 and aseparately formed face plate 14. The face plate is preferably weldedabout its periphery to a front 16 of the body. A weight member 18 isinserted into a recess 20 formed at a rear 22 of the body. Upon finalassembly of the club head 10, an annular mass 24 of the body and a rearsurface 26 of the face plate form a main cavity 28 at the rear (see FIG.3). The weight distribution profile of the club head can be adapted toaccommodate requirements of an individual type of golfer.

[0019] With reference to FIGS. 1 and 2, the annular mass 24 of the bodycomprises a heel portion 36, a toe portion 38, a top portion 40 and abottom portion 42. In each embodiment, the annular mass defines aninternal chamber in at least part of the top portion to promote arelatively lower center of gravity (CG) for the club head. As shown inthe embodiment of FIG. 1, a single chamber 44 is formed that extendsthrough a majority of the top portion and into the toe portion. In thisembodiment, the chamber is left hollow. Although, in other embodiments,any of a number of materials having a density different than the body,such as a polymer, a foam or a high density filler, for example, can beused to fill the chamber to obtain desired weight distribution andperformance characteristics.

[0020] In the embodiment of FIG. 2, multiple chambers 44 partitioned bywalls 46 are defined in the top and toe portions 40, 38. The walls arerelatively thin, each having about the same thickness and also serve tofurther reinforce the club head. Beneficially, the inclusion of thewalls does not significantly increase the mass in the toe or topportion. Thus, the CG of the club head is still effectively low comparedto solid toe and/or top portions. In other embodiments, one or more ofthe walls can be substantially thicker, even having a thicknesscomparable to the length of one of the chambers depicted in FIG. 2. Thechambers can also be located or extended into one or both of the heeland toe portions 36, 38, as desired.

[0021] In certain applications, it is desirable to selectively fill oneor more chambers 44 with a material having a different density forfurther mass management or for vibration dampening. For example, ifselected chambers about the heel end are filled, then the CG ispositioned toward the heel. The resultant low, heelward CG location ispreferred by many players for the increased ease in launching a golfball and right to left ball flight. Alternatively, heel and toe endchambers can be filled while keeping the central chambers in the topportion hollow to achieve increased heel and toe weighting. Selectedchambers can be filled by the manufacturer to accommodate needs of aparticular skill level of golfers, or even, to personalize the club headto the needs of an individual golfer.

[0022] With reference to FIG. 3, the weight member 18 aids in promotinga low CG for the club head. The weight member preferably has a polymerichousing 30 with at least one high density element 32 enclosed therein.The weight member is configured to be securely received in the recess20. In this embodiment, the weight member is removably affixed by acombination of a locking lip 34 and/or adhesive. Alternatively, theweight member may be affixed using tabs formed on the housing that arepressed into grooves formed in the walls of the recess. The weightmember can also be attached using other methods known to those skilledin the art. The weight member can comprise a cartridge as disclosed ineither of Applicants' co-pending U.S. application Ser. No. 09/728,955filed Dec. 1, 2000 entitled GOLF CLUB HEAD or U.S. application Ser. No.10/234,663 filed Sep. 3, 2002 entitled GOLF CLUB HEAD, the disclosuresof both being incorporated herein. In the embodiment depicted in FIG. 4,a separate weight member is not included.

[0023]FIGS. 3 and 4 show club heads formed in two preferred methods ofthe present invention. The material of the club head can comprise anymetal, such as from the group of steel alloys, aluminum alloys andtitanium alloys, for example. The body 12 and the face plate 14 can bethe same or different, and the attachment of the face plate 14 cancomprise welding or another method known to those skilled in the art. Inone preferred embodiment, a body is formed of 17-4 stainless steel and aface is formed of a high strength steel alloy such as Carpenter Custom455®. Alternatively, one of the body 12 and the face plate 14 cancomprise a non-metallic material.

[0024] With reference to FIG. 3, the separate face plate 14 is attachedto the front 16 of the body 12 and encloses the chamber 44. The faceplate 14 can be stamped, forged, cold rolled or formed using any knowntechnique. Any filler material for the chamber 44 can be added prior tothe attachment of the face plate. The weight member 18 is preferablyattached to the body after the face plate. Alternatively, the weightmember can be omitted.

[0025] With reference to FIG. 4, a face plate 14 is integrally formedwith the body 12. The chamber 44 is created using any technique known tothose skilled in the art, such as employing ceramic cores, soluble coresor pick-outs. A preferred method utilizes a mold such as shown in FIGS.5 and 6 wherein a soluble core is used.

[0026] In this method, a mold 50 is provided for a body 12 having afront and a rear, the rear having a top portion, a toe portion, a heelportion and a bottom portion. At least one soluble core 52 is placed ina region of the mold corresponding to at least the top portion of thebody. The number and/or configuration of the soluble cores used createthe desired chamber or chambers. The mold is filled with a hot wax thatforms the pattern for the club head. The soluble core is removed throughan aperture 54 left in the club head wax pattern. The club head is thencreated by well-known investment casting process, and the aperture isclosed off to form the one or more chambers. Prior to closing theaperture, a material having a density different than the material of thebody can be introduced through the aperture into the chamber.

[0027] It should be appreciated from the foregoing that the presentinvention provides an iron-type golf club head having a face platedefining a striking face of the club head and a body having an annularmass disposed behind the striking face. The annular mass extends about aperiphery of the face plate defining an external cavity centrallylocated on a rear side of the face plate. The annular mass includes atop portion extending along a top edge of the face plate, a toe portionextending along a toe edge of the face plate, a heel portion, and abottom portion. A single, elongated internal chamber or a plurality ofchambers are provided and are preferably cast within the rear of theclub head. At least one internal chamber is located adjacent to the topedge, as defined by the top portion of annular mass. The internalchamber, or a selected number of a plurality of chambers defined by theannular mass, can be filled to further manage the weight distribution ofthe club head. Thus, the club head can be tuned to accommodaterequirements of an individual golfer.

[0028] Although the invention has been disclosed in detail withreference only to the preferred embodiments, those skilled in the artwill appreciate that additional composite faces for golf club heads andmethods for manufacturing golf club faces can be included withoutdeparting from the scope of the invention. Accordingly, the invention isdefined only by the claims set forth below.

We claim:
 1. An iron-type golf club head comprising: a face plate havinga front side defining a striking face of the club head and having a topedge and a toe edge; and a body having an annular mass disposed behindthe striking face, the annular mass extending about a periphery of theface plate thereby defining an external cavity centrally located on arear side of the face plate, the annular mass including a top portionextending along the top edge of the face plate, a toe portion extendingalong the toe edge of the face plate, a heel portion, and a bottomportion, and at least a portion of the top portion defining an internalchamber located adjacent to the top edge.
 2. A golf club head as definedin claim 1, wherein the face plate is integrally formed with the body ofthe club head.
 3. A golf club head as defined in claim 1, wherein theinternal chamber extends substantially the entire length of the topportion, and the toe portion defines a portion of the internal chambersuch that the internal chamber further extends at least partially intothe toe portion of the annular mass.
 4. A golf club head as defined inclaim 1, wherein the club head further comprises a weight memberinserted into a recess defined by the bottom portion of the annularmass.
 5. A golf club head as defined in claim 1, wherein at least partof the body or the face plate is formed of non-metallic material.
 6. Agolf club head as defined in claim 1, wherein the annular mass furtherdefines a second internal chamber located along the top portion and/orthe toe portion thereof.
 7. A golf club head as defined in claim 6,wherein the volume of the first internal chamber is substantially thesame as the volume of the second internal chamber.
 8. A golf club headas defined in claim 6, further comprising a filler material locatedwithin one of the internal chambers, the filler material having adensity different than a density of the material of the body of the clubhead.
 9. A golf club head as defined in claim 1, wherein the face plateis separately formed and attached to the front of the club head.
 10. Agolf club head as defined in claim 9, wherein the body and the faceplate are each formed of metallic material chosen from at least one in agroup consisting of steel alloys, aluminum alloys, and titanium alloys.11. A method of manufacturing an iron-type golf club head, comprising:casting a body of a metallic material having a front and a back, thebody having an annular mass defining a central opening, the annular massincluding a top portion, a toe portion, a heel portion, and a bottomportion, the top portion defining a recess opened toward the front ofthe body; forming a face plate sized to conform with the front of thebody; and attaching the face plate to the front of the body therebyenclosing the recess and forming an internal chamber adjacent to a topedge of the club head.
 12. A method as defined in claim 11, wherein theannular mass further defines a second internal chamber located along thetop portion and/or the toe portion thereof.
 13. A method as defined inclaim 11, wherein the internal chamber extends substantially the entirelength of the top portion, and the toe portion defines a portion of therecess such that the internal chamber further extends at least partiallyinto the toe portion of the annular mass.
 14. A method as defined inclaim 11, further comprising filling the recess with a material having adensity different than a density of the metallic material of the bodyprior to attachment of the face plate.
 15. A method as defined in claim11, further comprising attaching a weight member to the body into arecess defined by the bottom portion for the annular mass.
 16. A methodof manufacturing a golf club head, comprising: providing a mold for aclub head having a striking face and a body disposed behind the strikingface, the body including an annular mass having a top portion, a toeportion, a heel portion and a bottom portion, the annular mass definingperipheral boundaries of a cavity on the rear of the body; placing atleast one soluble core in a region of the mold corresponding to at leastthe top portion; filling the mold with a hot wax to form a wax pattern;removing the at least one soluble core through an aperture in the waxpattern; and casting a club head from the wax pattern by an investmentcasting process, the resulting club head having an internal chamber inat least at the top portion of the annular mass of the body.
 17. Amethod as defined in claim 16, wherein the at least one soluble core isused such that at least two chambers are formed in the body.
 18. Amethod as defined in claim 16, wherein the at least one soluble coreextends at least partly into the toe portion of the mold.
 19. A methodas defined in claim 16, further comprising filling the internal chamberwith a material having a density different than the material of the clubhead.
 20. A method as defined in claim 16, further comprising attachinga weight member to the body.
 21. A method of manufacturing an iron-typegolf club head, comprising: providing a mold for a club head having astriking face and a body disposed behind the striking face, the bodyincluding an annular mass having a top portion, a toe portion, a heelportion and a bottom portion, the annular mass defining peripheralboundaries of a cavity on the rear of the body; providing at least onehollow portion in at least the top portion of the body of the club head;and forming a club head having an internal chamber in at least the topportion of the annular mass of the body.
 22. A method as defined inclaim 21, further comprising using at least one ceramic core to providethe at least one hollow portion at least the top portion of the body ofthe club head.